Oval
sea grapes seaweedCaulerpa racemosa*Family Caulerpaceaeupdated
Jan 13Where
seen? This juicy looking seaweed is made up of little balls
and is commonly seen on our Southern shores on rocks and coral rubble
in small clumps. In Singapore, it does not form extensive blooms.
Elsewhere, it is said to form meadows in front of mangroves.

Features: The seaweed resembles
bunches of little grapes. Each bunch about 2-8cm long, with bead-like
shapes (the 'grapes') arranged on a vertical 'stem'. The 'grape' (about
0.5cm diameter) spherical or club shaped with rounded tips. The shapes
may be densely or sparsely packed. These bunches of 'grapes' emerge
from a long horizontal 'stem' that creeps over hard surfaces or just
under the sand. It grows on coral rubble or on rocks, sometimes extending
onto the sand. Colours range from green to yellowish-green and bluish-green.

Some other Caulerpa species may take forms that resemble Oval sea
grapes. These include Caulerpa peltata, Caulerpa macrophysa.
There are varieties of Caulerpa racemosa with bell-shaped
tips (Caulerpa racemosa var turbinata) or flat like
little umbrellas (Caulerpa racemosa
var peltata).

Human uses: This seaweed is eaten
in some places. In the Philippines, it is eaten fresh as a
salad, or salted so it can be eaten later. Small quantities are also
exported to Japan. It is also eaten in Malaysia and Indonesia. It
is also reported to have antibacterial and antifungal properties,
and to be used to treat high blood pressure and rheumatism. The seaweed
is also fed to livestock and fish. However, some Caulerpa species
produce toxins to protect themselves from browsing fish. This also
makes them toxic to humans.

This seaweed is considered an alien invasive species in the Mediterranean.

Lim, S.,
P. Ng, L. Tan, & W. Y. Chin, 1994. Rhythm of the Sea:
The Life and Times of Labrador Beach. Division of Biology,
School of Science, Nanyang Technological University & Department
of Zoology, the National University of Singapore. 160 pp.